Comparing lengths by measuring · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.
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Comparing lengths by measuring

Mathematics · Measurement · ages 7-8
Name ______________________   Date ____________

  1. A ribbon is 14 cm and a string is 6 cm. How much longer is the ribbon?

    String6Ribbon14
    • 6 cm
    • 20 cm
    • 8 cm

  2. A book's width is recorded in inches. A box's width is recorded in centimetres. What must you do before subtracting the measurements?

    • Measure both widths in the same unit
    • Subtract the numbers and keep both units
    • Use the larger number without its unit
    • Add the numbers and call the total cm

  3. Two ribbons each measure 18 cm long. What is the difference between their lengths in centimetres?

    Answer: ______________

  4. Sam measures a crayon and a pencil. The crayon is 9 cm and the pencil is 16 cm. Which subtraction shows how much longer the pencil is?

    Crayon9Pencil16
    • 9 − 16
    • 16 − 9
    • 16 + 9

  5. A scarf is 32 cm and a belt is 18 cm. Which sentence correctly tells the length difference?

    Belt18Scarf32
    • The scarf is 14 cm longer than the belt
    • The scarf is 50 cm longer than the belt
    • The belt is 14 cm longer than the scarf

  6. A desk is 70 cm tall. A chair is 45 cm tall. How much taller is the desk than the chair?

    Chair45Desk70
    • 20 cm
    • 25 cm
    • 30 cm

  7. A desk is 60 cm tall. A bookshelf is 18 cm taller than the desk. How tall is the bookshelf?

    • 42 cm tall
    • 78 cm tall
    • 18 cm tall
    • 60 cm tall

  8. A shelf is 45 cm long. A box is 28 cm long. How many centimeters longer is the shelf?

    Box28Shelf45

    Answer: ______________

  9. Omar wants to know exactly how much taller a bookshelf is than a desk. He looks at them and says, 'The bookshelf is bigger.' What should he do next?

    • Weigh both objects and subtract their weights
    • Count the books and compare their cover sizes
    • Measure both heights in cm and subtract

  10. A curtain is 120 cm and a towel is 45 cm. The difference between them is 85 cm.

    Towel45Curtain120

    Circle one:   True   False

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Answer key

For grown-ups. Fold this page away before handing over the rest.

Comparing lengths by measuring W1-mt_xWg0lI_gG4-s1

  1. 8 cm · 14 - 6 = 8, so the ribbon is 8 cm longer.
  2. Measure both widths in the same unit · The measurements count different-sized units. Measure both widths in the same unit before finding their difference.
  3. 0 · 18 - 18 = 0. Equal lengths have a difference of 0 cm.
  4. 16 − 9 · The pencil is longer, so start with 16 and take away 9. 16 − 9 = 7, so the pencil is 7 cm longer.
  5. The scarf is 14 cm longer than the belt · 32 - 18 = 14. The scarf is 14 cm longer, and saying 'longer' with the unit makes the answer clear.
  6. 25 cm · 70 - 45 = 25, so the desk is 25 cm taller than the chair.
  7. 78 cm tall · Add the height difference to the desk's height: 60 + 18 = 78 cm.
  8. 17 · 45 - 28 = 17. The shelf is 17 cm longer than the box.
  9. Measure both heights in cm and subtract · Looking can suggest which object is taller. To find the exact height difference, measure both heights in the same unit and subtract.
  10. False · The gap from 45 cm to 120 cm is 5 + 50 + 20 = 75 cm. The claimed 85 cm difference does not match.
Worksheet · LightMySky